Glycogen synthase kinase 3 (GSK3) inhibition: a potential therapeutic strategy for Alzheimer's disease

Recent Advances in Mass Spectrometry-Based Studies of Post-translational Modifications in Alzheimer's Disease

Alzheimer's disease (AD) is a progressive neurodegenerative disorder characterized by cognitive decline. There are over 10 million new cases of AD each year worldwide, implying one new case every 3.2 seconds. Post-translational modifications (PTMs) such as phosphorylation, glycosylation, and citrullination have emerged as key modulators of protein function in AD, influencing protein aggregation, clearance, and toxicity. Mass spectrometry (MS) has become an indispensable tool for detecting and quantifying these PTMs, offering valuable insights into their role in AD pathogenesis. This review explores recent advancements in MS-based studies of PTMs in AD, with emphasis on MS techniques like data-dependent acquisition (DDA) and data-independent acquisition (DIA), as well as enrichment methods used to characterize PTMs. The applications of these MS-based approaches to the study of various PTMs are highlighted, which have significantly accelerated the biomarker discovery process, providing new avenues for early diagnosis and therapeutic targeting. Advances in biological understanding and analytical techniques, while addressing the challenges and future directions, will be discussed.

Exploring the Neuroprotective Properties of Celery (Apium graveolens Linn) Extract Against Amyloid-Beta Toxicity and Enzymes Associated with Alzheimer's Disease

Celery (Apium graveolens L.), one of the numerous members of the Apiaceae family, has been traditionally used as food and medicine due to its nutraceutical properties. Nevertheless, understanding the neuroprotective effects of this species requires evaluation through different mechanisms relevant to Alzheimer's disease (AD) treatment. This study explored the neuroprotective potential of ethanolic extracts of celery leaves. Liquid chromatography and mass spectrometry-based metabolomics analysis of the extract revealed the existence of a diverse array of secondary metabolites, including phenolic acids, hydroxycinnamic acid, flavonoids, flavonoid O-glycosides, flavonol, glycosides, and isoflavones. Celery extract protects human neuroblastoma SH-SY5Y cells against 15 µM amyloid-beta (Aβ1-42) toxicity, enhancing their vitality from 67% to 81.74% at 100 µg/mL. The extract inhibited the enzymes associated with AD, including acetylcholinesterase (AChE), butyrylcholinesterase (BChE), glycogen synthase kinase 3 beta (GSK3β), cyclooxygenase 1 (COX-1), and cyclooxygenase 2 (COX-2) with IC50 values of 21.84, 61.27, 45.94, 34.1, and 52.2 µg/mL, respectively. In conclusion, celery leaf extract components may be potential therapeutic candidates for AD prevention and treatment.

Development of donepezil hydrochloride-loaded PLGA-based nanoparticles for Alzheimer's disease treatment

In recent years, nanoparticle (NP) systems have demonstrated significant promise in pharmaceutical applications. This study focused on the development of donepezil hydrochloride-loaded PLGA-NPs, prepared using the 'Double Emulsion Solvent Evaporation' method. The impact of varying concentrations of polyvinyl alcohol-(PVA) in the aqueous phase and sonication time on NP characteristics was comprehensively examined. Results showed that increasing PVA concentration and sonication time resulted in a reduction in NP size, with an optimal formulation (I-DNP) achieving a particle size of 136.37 nm ± 0.93 and a PDI of 0.122 ± 0.011, indicating uniformity. The zeta potential was measured at - 24.17mV ± 1.21, confirming the electrostatic stability of the formulation, essential for long-term stability. Trehalose was incorporated to enhance stability, and gastrointestinal stability testing revealed that I-DNP degraded faster in acidic environments. The encapsulation efficiency reached 69.22 ± 4.84%, suggesting effective drug loading, and release studies exhibited a sustained release profile, with a Fickian and non-Fickian release mechanism. DSC, FT-IR, and 1H-NMR analyses confirmed the encapsulation and structural integrity of the formulation. In biological activity studies, I-DNP exhibited potent anti-AChE and anti-BuChE activities, with Chorioallantoic Membrane (CAM) assays showing significant inhibition of angiogenesis. These findings highlight the potential of I-DNP as a promising therapeutic strategy for Alzheimer's disease, demonstrating its ability to enhance drug stability, controlled release, and potential blood-brain barrier (BBB) penetration. Future studies will focus on long-term stability testing and in vivo Alzheimer's models to further validate its clinical applicability. This research contributes to the advancement of nanoparticle-based drug delivery systems for neurodegenerative diseases, paving the way for innovative therapeutic approaches.

The Mechanisms of Lithium Action: The Old and New Findings

Despite lithium's presence in modern psychiatry for three-quarters of a century, the mechanisms of its therapeutic action have not been fully elucidated. This article presents the evolution of the views on these mechanisms, and both the old and new findings are discussed. Among the old mechanisms, lithium's effect on the purinergic system; electrolyte metabolism; membrane transport; and second messenger systems, namely, cyclic nucleotide and phosphatidylinositol (PI), glycogen synthase kinase-3beta (GSK-3β), brain-derived neurotrophic factor, and neurotransmitters, are discussed. The new data were obtained from in vitro studies, molecular biology, and genetic research. They showed the effects of lithium on the immune system, biological rhythms, telomere functions, and mitochondria. In this article, each lithium mechanism is considered in the light of its association with the pathogenesis of bipolar disorder or/and as a marker of the lithium response. Although not exhaustive, this review elucidates the multiple potential mechanisms of lithium action. It was also observed that many seemingly "old" mechanisms have experienced a resurgence in research conducted during the 21st century. Additionally, many studies converged on the previously postulated mechanisms of lithium inhibiting GSK-3β and PI.